Bio marks

Question 1

Statins

Answer 1

Drugs which lower cholesterol in the blood

Question 2

Digestive enzymes

Answer 2

Lipase breaks fats into fatty acids and glycerol
Protease breaks protein into amino acids
Amylase breaks starch into sugar

Question 3

Alveoli diffusion

Answer 3

WALLS are one cell thin, efficient blood supply

Question 4

Benedict’s test

Answer 4

Blue -> Orange
Tests for sugar/glucose
Benedict’s reagent added to sample and placed in water bath

Question 5

Iodine test

Answer 5

Orange -> Dark Blue
Tests for starch
Iodine solution added to food sample (made with pestle and mortar)

Question 6

Biuret reagent

Answer 6

Blue-> Purple
Tests for protein
Biuret reagent added to food sample and shake test tube

Question 7

Risk factor of food tests

Answer 7

Solutions like iodine or benedict’s reagent are IRRITANTS so gloves
Reagent could spit into eyes during water bath so goggles

Question 8

What strengthens Xylem tissue

Answer 8

Lignin and cellulose

Question 9

What tissue can differentiate through the life cycle of a plant

Answer 9

Meristem

Question 10

What process transports dissolved substances around a plant

Answer 10

Translocation

Question 11

Tips for 6 markers

Answer 11

Include REPEAT to find MEAN
Include CONTROL variables

Question 12

Why does a high concentration of salt solution mean larger loss in mass of potato

Answer 12

Concentration of water in salt solution is lower than in the potato so water leaves the potato by osmosis (diffusion through partially permeable)

Question 13

How to tell if bacteria aren’t resistant against antibiotic in petri dish practical

Answer 13

Antibiotic will have a ZONE OF INHIBITION around it meaning the bacteria is getting killed

Question 14

2 effects of antibiotic resistance

Answer 14

Diseases become more common and they can no longer be treated using antibiotics

Question 15

Why is it hard to develop drugs which destroy viruses

Answer 15

Drugs can harm living cells
Viruses mutant frequently

Question 16

How is starch made in plants

Answer 16

Glucose from photosynthesis converted to starch

Question 17

What subcellular structure in plants absorbs sunlight

Answer 17

Chloroplasts which contain chlorophyll

Question 18

What causes yellow colour in leaves and what term is given to this

Answer 18

Ion deficiency like nitrate is called chlorosis

Question 19

Magnification formula and what tip to remember

Answer 19

Image size/Real size
Don’t forget to convert units
mm=1,000,000nm

Question 20

During mitosis what happens

Answer 20

Nucleus and other subcellular structures are duplicated. Fibres pull the duplicated material to different halves of the cell. The cell splits

Question 21

3 reasons for drug testing

Answer 21

Dosage, Toxicity, Efficacy

Question 22

Memory tricks for heart

Answer 22

Vein and Vena Cava on opposite sides. Artery and Right both have Rs.
Pacemaker in right atrium

Question 23

What does the coronary artery do

Answer 23

Transport oxygenated blood to the heart muscles

Question 24

How do salmonella bacteria cause vomiting and diaherea

Answer 24

Release toxins

Question 25

Antibodies

Answer 25

Produced by lymphocytes and are complimentary to antigens which they bind to. If infected again antibodies produced rapidly

Question 26

What is the relevance of 37 degrees

Answer 26

Many bacteria (food poisoning or infection) grow best at this temperature because it is body temperature

Question 27

How do antibiotics kill bacteria

Answer 27

Damage cell walls. Osmosis causes water to enter bacteria cell and wall can no longer withstand pressure so it bursts

Question 28

Why is a thin layer of onion epidermis used in microscopy

Answer 28

So light can penetrate it

Question 29

Why is iodine solution added to onion epidermis in microscopy

Answer 29

To stain subcellular structures

Question 30

Why is a cover slip put on onion at an angle in microscopy

Answer 30

To prevent air bubbles (cover slip holds in place)

Question 31

How can a drawing of a cell under a microscope be improved

Answer 31

Do not have gaps between cells Do not draw overlapping cells

Question 32

What cells control opening and closing of stomata

Answer 32

Guard cells

Question 33

Differences between transpiration (precipitation) and translocation

Answer 33

Transpiration - Xylem - Up - Water+Mineral ions Translocation- Phloem - Up+Down - Dissolved sugars

Question 34

What is transpiration

Answer 34

Evaporation of water through leaves

Question 35

Why do stomata open more at midday

Answer 35

There is more sunlight so they can photosynthesise more so they open to take in more CO2

Question 36

Correlation between volume and surface area:volume ratio

Answer 36

Inversely proportional

Question 37

Why does a larger surface area:volume ratio mean higher metabolic rate

Answer 37

Heat lost more easily due to surface area so respiration required to release heat energy. Respiration is large part of metabolism

Question 38

Remember for 6 marker compare questions...

Answer 38

SIMILARITIES and differences

Question 39

Animal cells are ... than plant cells

Answer 39

Smaller

Question 40

Why does an animal cell burst in beaker of water but plant doesn't

Answer 40

Osmosis causes water to enter and cells to swell but animal cell bursts because no cell wall

Question 41

Which diabetes is from unhealthy eating and lack of excercising

Answer 41

Type 2

Question 42

Products of anaerobic respiration in plant cells are...

Answer 42

Ethanol and CO2

Question 43

Differences of anaerobic and aerobic respiration

Answer 43

Release less energy No water produced Lactic acid (oxygen debt)

Question 44

Why would CO2 levels plateau on a CO2 time graph

Answer 44

Rate of respiration=Rate of photosynthesis

Question 45

Why is CO2 released when an organism dieds

Answer 45

Decomposed by bacteria which use respiration to release CO2

Question 46

Why is lock and key model specific for certain enzymes

Answer 46

Active site and substrates are complimentary

Question 47

Why do enzymes not work at low or high temperatures

Answer 47

Low conditions- enzyme and substrate molecules don't have enough energy for enough collisions High conditions- enzymes denature meaning active site changes shapes so substrate can't fit in anymore

Question 48

4 Factors affecting enzyme activity

Answer 48

pH Enzyme conc Substrate conc Temp

Question 49

What structure in a mesophyll cell isn't in a root hair cell

Answer 49

Chloroplast

Question 50

What is diffusion

Answer 50

The movement of particles from a high concentration to a low concentration

Question 51

+ Similarities between eukaryotic and prokaryotic cells

Answer 51

Cytoplasm Ribosomes Genetic material

Question 52

Protist vs Fungus vs Bacteria vs Virus What type of cells are they Pneumonic for size order

Answer 52

Protists and Fungi are eukaryotic - Bacteria is prokaryotic - Virus is acellular Protists and Fungi uni/multi - Bacteria unicellular - Virus is acellular Very Big Puffer Fish

Question 53

Treatments- Protist vs Fungus vs Bacteria vs Virus

Answer 53

Protist- Antimalarials Fungus- Antifungals Bacteria- Antibiotics Virus- Vaccines

Question 54

Platelets job

Answer 54

Form clots/scabs to prevent pathogens entering

Question 55

Factors for transpiration

Answer 55

H Temperature H Light intensity H Wind speed L Humidity

Question 56

Mechanical valve vs Biological valve

Answer 56

Both readily available Bio rejected and need to be replaced because wear out so further surgery Mech require medication forever which leads to bleeding if not taken

Question 57

Why does diabetes mean water travels out of cells

Answer 57

Diabetes means high blood glucose concentration (meaning less water in comparison to glucose) So water diffuses out of cells into blood through osmosis through a partially permeable membrane